A fire sparked early Monday at a medical imaging building in Fallbrook, officials said.
The North County Fire Protection District tweeted about the incident at around 6 a.m., saying East Alvarado Street and North Brandon Road was closed. Drivers were urged to use a different route.
According to officials, a fire had sparked just after 4 a.m. on the second floor of the commercial building. No one was inside at the time and no one was hurt.
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The investigation is ongoing; check back for updates on this developing story.